Zn-II-Dy-III single-molecule magnets constructed by salen-type ligand, acetate and beta-diketonate

A series of Zn-II-Dy-III complexes with molecular formula [LZn(CH3COO)Dy(hfac)(2)] (1), [LZn(CH3COO)(2)Dy(dbm)]center dot CH2Cl2 (2), [LZn(CH3COO)Dy(btfa)(2)]center dot CH2Cl2 (3), (H2L = N,N'-bis(3-methoxysalicylidene)-1,2-phenylenediamine, hfac = hexafluoroacetylacetone, dbm = dibenzoylmethane, btfa = benzoyltrifluoride acetone) were structurally and magnetically characterized. They have similar Zn-II-Dy-III structural cores bridged by N and O atoms of the hexadentate salen type ligand (L). The main difference between them is the peripheral beta-diketonate co-ligands surrounding Dy-III ion. Dynamic magnetic properties measurements revealed that complexes 1-3 exhibit the field-induced SMM behavior with relaxation energy barriers U-eff/k(B) of 45.49 K, 69.28 K and 101.34 K, respectively. The ac magnetic susceptibility of diluted sample 3Dy(0.05)Y(0.95) confirmed the single molecule original relaxation, in which the quantum tunneling of magnetization (QTM) was suppressed efficiently and a butterfly-shaped hysteresis loop at 1.8 K was observed. (C) 2022 Elsevier B.V. All rights reserved.